China’s Sinopharm Covid-19 vaccines – one of which is available in the UAE – are less effective against the South African variant but do still offer significant protection.
Results from laboratory studies tally with findings from other coronavirus vaccines, several of which have also been shown to have lower efficacy against the more contagious form of the deadly pathogen.
Chinese researchers found that serum, a fluid component of blood, collected from a dozen people given a Sinopharm vaccine was able to neutralise the South African variant.
The protective effect was, however, weaker compared with that against the original coronavirus, a result of the South African variant having spike protein mutations that make it harder for the immune system of vaccinated people to recognise the pathogen.
Prof Paul Hunter, an infectious diseases specialist at the University of East Anglia in Britain, said that even if vaccines offered slightly weaker protection against the South African variant, having one was still “tonnes better” than not being immunised.
“At the moment the evidence is still that they’re pretty good at stopping you getting severe disease, even if they may be less effective at stopping you getting mild disease,” he said.
“I don’t think we’ll ever stop the infection spreading, but if we can stop people getting severely ill and being admitted to hospital and dying, that’s good enough for me.”
The Sinopharm vaccine is being used throughout the UAE, while in Dubai the Pfizer-BioNTech vaccine and the Oxford-AstraZeneca vaccine are also approved for widespread use.
The UAE’s rapid immunisation programme has resulted in the country having one of the highest per capita Covid-19 vaccination rates in the world.
The Pfizer-BioNTech, Moderna, Novavax and Johnson & Johnson vaccines, the last two of which are expected to be released for global use soon, have like the Sinopharm shots also been shown to be less effective against the South African variant.
Novavax aims to develop a new form of its vaccine better able to fight infection with the South African variant and could offer a booster shot alongside its original vaccine, a strategy also announced by Moderna. Sinopharm said Phase 3 trials of the vaccine found it was 79 per cent effective against Covid-19.
The test to determine the protection against new variants was to mix blood serum from people given the vaccine with the virus and look at the reaction. There was a reduced reaction against the South African variant, but it is not something that can be used to directly give an efficacy rate.
Experts have previously said the Chinese vaccines, which are based on inactivated forms of the coronavirus, could be redesigned to cope with new variants in about two months.
Vaccines have also been found to be less effective against the UK variant, which has spread widely, although typically the reduction has been less than that seen with the South African variant.
While both variants share a mutation called N501Y, the South African form has additional mutations, including an important one called E484K.